Sun Nuclear 1028XP - sale

I am selling two Sun Nuclear 1028XPs. I will no longer be offering radon testing services so I need to sell these. They haven’t seen much use but they are truly fantastic units. Both are currently calibrated.

How much, what is their age, and when does the calibration expire?

$1,500 OBO for the pair. Purchased in 2020. One was just calibrated. The other is December.